Advanced LIGO subsystems
are the organizational units of the overall project. Follow the links below to view the mission and progress of each subsystem.
Auxiliary Optics | Core Optics |
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Data Acquisition | Data and Computing Systems |
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Facilities Modifications |
Input Optics |
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Interferometer Control |
Pre-Stabilized Laser |
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Seismic Isolation |
Suspensions |
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Advanced LIGO News
Livingston Pre-Stabilized Laser Installation Reaches Completion
May 2011
Some photos courtesy of AEI/LZH
Personnel from the Albert Einstein Institute (AEI), Laser Zentrum Hannover (LZH) and LIGO finished the installation of the Livingston detector (L1) Advanced LIGO laser system (PSL -- pre-stabilized laser) in the late spring of 2011. LIGO will now embark on a commissioning program to optimize the system's day-to-day performance and integrate the PSL with the detector's vacuum input optics that have yet to be installed. The Max Planck Institute for Gravitational Wave Research/Albert Einstein Institute in Hannover supplies the Advanced LIGO laser systems for the L1, H2 and H1 detectors and a fourth for research and characterization as a German contribution to the aLIGO international partnership. The industrial partner LZH has collaborated with MPI/AEI to manufacture the lasers and participate in their characterization and installation.
The photo above shows most of the the major PSL components. Moving from left to right in the photo, the first large encasement contains the 2-Watt non-planar ring oscillator (NPRO) and a medium power stage that boost the light power to 35 W. The large blue-trimmed case, the high-power amplifier, contains four end-pumped laser heads. Each laser head is pumped by seven 45 W laser diodes. These pump diodes rest in a separate room outside of the PSL enclosure; their light enters the amplifier through optical fibers. The high power amplifier brings the beam power to 180 W. To the right of the amplifier sits a black case that contains a set of diagnostic electronics. The nearby white enclosure contains a resonant cavity that passes the beam through a bow-tie path for filtering. The large yellow cylinder houses the reference cavity, another rigid resonant cavity that acts as a frequency reference for the main laser. Finally, the periscope on the table's distant corner will contain the mirrors that reflect the beam through a light pipe and into the vacuum system.
Image 1: The nearly-bare PSL table inside the new aLIGO enclosure at LIGO Livingston
Image 2: Moving the high power amplifier into position
Image 3: A nice view of the uncovered reference cavity
Image 4: Populating the PSL table
Image 5: A view of the NPRO and the medium power stage
Image 6: A rack in the pump diode room
aLIGO News Archive
August 2016 -- LIGO Reports O1 Results
June 2016 -- Another Black Hole Merger
Feburary 2016 -- First Gravitational Wave Detection
November 2015 -- O1 Progress Report
August 2015 -- Final Preparations for the O1 Run
February 2015 -- Hanford's H1 Achieves Two-Hour Lock
July 2014 -- Livingston Commissioning Progress
June 2014 -- Livingston Locks the L1 Interferometer
December 2013 -- Livingston Installs End Station Payloads
September 2013 -- Half-interferometer Test Closes
June 2013 -- DRMI Test at Livingston
May 2013 -- Arm Length Stabilization
November 2012 -- One-arm Test at Hanford
September 2012 -- LIGO Begins Locking Optical Cavities
August 2012 -- Installation of Stray Light Controls
July 2012 -- Small Optic Suspenions Enter L1
April 2012 -- First Cartridges Enter the Vacuum
November 2011 -- Glass Fiber Suspensions in Production
October 2011 -- Continued Suspension Development
July 2011 -- Hanford's H2 Becomes a 4K
May 2011 -- LLO Laser Installation Completed
March 2011 -- Input and Output Tubes Undergo Removal
February 2011 -- New Laser Enclosure Takes Shape
December 2010 -- Initial LIGO Comes Out of the Vacuum
October 2010 -- S6 Yields to Advanced LIGO
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